Certain Nutrients Bad for Pregnant Women, Hopkins Study Warns

Vitamins are good, right? Well, it’s complicated, according to new research out of Johns Hopkins.

As if pregnant women didn’t need another thing to feel nervous about, now scientists are warning that too much of certain nutrients — namely folate and B12 — is associated with higher rates of autism. Sometimes seriously higher: The children of women who had very high levels of both nutrients right after giving birth had a 17.6 times greater risk of developing an autism spectrum disorder. But at the same time, normal levels of folic acid are good, in that they help protect a developing fetus’s brain; levels of folate that are too low have been linked to certain birth defects. (There have been some good questions raised about the Hopkins study as well.)

One big question: Why did some of the women in the study end up with such high levels of these nutrients in their blood supply? Many of the women who participated were taking a multivitamin, but that doesn’t account for the differences in nutrient levels among them. Researchers theorize that some of the women may absorb folate more fully, and/or metabolize it more slowly; they may also have eaten more folate-rich foods during pregnancy.

“We tell women to be sure to get folate early in pregnancy. What we need to figure out now is whether there should be additional recommendations about just what an optimal dose is throughout pregnancy,” lead author Ramkripa Raghavan of the Bloomberg School of Public Health told the Hopkins Hub.